The influence of the carbon support and Platinum particle size on degradation of cathode for low Platinum-loading catalyst layer

摘要

We demonstrated the ability to control the platinum particle size in the synthesis of carbon supported Pt (Pt/C) electrocatalyst with reactive spray deposition technology (RSDT). The degradation of Pt cathode with loading of 0.1 mg/cm~2 in membrane electrode assembly (MEA) under simulated drive cycles (30000 triangular wave cycles between 0.6 and 1.0 V_(rhe)) showed similar electrochemical surface area (ECSA) at the end of life (EOL), regardless of the initial Pt particle size or carbon support type. However, it is possible to reduce the loss of ECSA using a gradient catalyst layer consisting of a 6 μm layer with Pt particles of 5 nm toward the membrane and another 6 μm layer with Pt particles of 2 nm toward the GDL. Microscopy studies suggested that the gradient catalyst layer have less Pt loss% into the electrolyte, thereby maintained higher ECSA at EOL.